Field of the Invention
The present invention relates to a honeycomb structure, a manufacturing method for the honeycomb structure, and a canning structure. More particularly, it relates to a honeycomb structure which is prevented from shifting in a can body when the honeycomb structure is stored in the can body which stores the honeycomb structure, and is excellent in thermal shock resistance and is easy to be manufactured, a manufacturing method for the honeycomb structure and a canning structure in which such a honeycomb structure is stored in a can body.
Description of the Related Art
A honeycomb structure is broadly used as a filter, a catalyst carrier or the like, and is broadly used especially as a catalyst carrier, a filter or the like for exhaust gas purification or exhaust gas treatment of an internal combustion engine such as a gasoline engine or a diesel engine, or a combustion device.
In particular, for the honeycomb structure to be used in the catalyst carrier, the filter or the like for exhaust gas purification of a gasoline engine car, a diesel engine car or the like, improvement of a purification performance is required to cope with exhaust gas regulations enhanced annually due to considerations of environment problems. On the other hand, as the honeycomb structure, weight reduction is required to increase a temperature rising rate of a catalyst, thereby activating the catalyst in early stages. On the other hand, from the aspect of engine development, a tendency to orientation for low power consumption and high output is remarkably indicated, and to cope with such a situation, decrease of a pressure loss is also required for the honeycomb structure. Additionally, for the purpose of using the honeycomb structure as the filter continuously for a long period of time, it is necessary to burn and remove a particulate matter (hereinafter called “PM” sometimes) deposited in the honeycomb structure. Also from the aspect of a combustion efficiency of this particulate matter, the honeycomb structure more preferably has a lower heat capacity and the weight reduction is required. Furthermore, in a case where the honeycomb structure is used as a catalyst loading filter, it is also required to increase an amount of the catalyst to be loaded, for the improvement of the purification performance. Heretofore, such a honeycomb structure has been used in a state where the honeycomb structure is stored in a can body which stores the honeycomb structure (hereinafter referred to as “canning” sometimes).
Such a problem as mentioned above is solved by decreasing a thickness of partition walls of the honeycomb structure or increasing a porosity of a substrate. For example, as a honeycomb structure of a high porosity, there has been suggested a honeycomb structure made of a material including cordierite whose pore distribution is controlled as a main crystal phase (e.g., see Patent Document 1). Additionally, for the purpose of increasing a shape accuracy of the honeycomb structure and improving its canning properties into a can body, there is disclosed a technology of machining an outer peripheral portion of the honeycomb structure and additionally applying a circumferential coating material to form a circumferential wall (e.g., see Patent Document 2).                [Patent Document 1] JP-A-2002-219319        [Patent Document 2] JP-A-H03-275309        